Bug in cpio involving -A and -D

[David Garfield]

When using options -A and -D, where the directory is not absolute, cpio
(usually) fails.  The problem is that it tries to chdir() into the
directory *twice*.  This only works if the path is absolute, or if the
directory name is appropriately symlinked.

I initially found this in the debian bullseye build of 2.13.  

I then downloaded the standard source and tried that as well.  (This
was made more difficult by the erroneous double definition of variable
program_name.)

My test script is below.  The expected output is a listing of all four
files added to the cpio.  The actual output is that file "2" does not
get added, and an error message reading "cpio: cannot change to
directory `d': No such file or directory" is output.

--David Garfield



#!/bin/bash

cpio="${1:-cpio}"

( rm -f d/1 d/2 d/3 d/4 d/d ; rmdir d ) >/dev/null 2>&1

mkdir d
echo 1 >d/1
echo 2 >d/2
echo 3 >d/3
echo 4 >d/4

echo 1 | $cpio -o -Hnewc    -Fout -Dd
echo 2 | $cpio -o -Hnewc -A -Fout -Dd
echo 3 | $cpio -o -Hnewc -A -Fout -D`pwd`/d
ln -s . d/d
echo 4 | $cpio -o -Hnewc -A -Fout -Dd

$cpio -itv -Fout